Multiply trick

Today our class watched a simple maths trick video. It said that you can multiply by drawing lines. First, if you have an equation that is 16 by 11, you first take the 1 from 16 so draw one line horizontally in the middle and take the 6 from 16 and draw 6 lines by 1 line leaving some space between the two. Next, for the 11, draw one line the opposite way from 16. Then draw another line leaving the space between them. After that, you have to divide it to 3 sections. Draw the dots where the lines meet across and then draw a semicircle on the far left dot and far right dots. Add the numbers of the dots section by section. So it would be one on the left side and 7 in the middle and 6 on right. The answer would be 176.

Here is what I did.

This is the link of the video.

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